1. Field of the Invention
The present invention relates generally to the field of beverage retaining and dispensing devices. More specifically the present invention relates to a safety drinking straw including a beverage delivery tube having a tube first end for insertion into a quantity of beverage and a tube second end for placement between user lips, the delivery tube containing a debris blocking structure substantially at the tube first end permitting a free flow of the beverage through the delivery tube while preventing entry of debris of a selected minimum target size into the delivery tube. The placement of the debris blocking structure substantially at the tube first end includes placement at or immediately adjacent to the tube first end and is a key feature of the present invention because this construction not only prevents debris from passing through the delivery tube, but prevents the debris from entering the delivery tube altogether so that the debris cannot lodge and become an obstruction within the tube.
The debris blocking structure preferably has a line profile in lateral cross-section across the tube first end to minimize flow resistance. One preferred embodiment of the debris blocking structure providing such a line profile includes at least one tube partition extending longitudinally from the tube first end along at least part of the tube length, and optionally along the entire tube length to reach the tube second end. The tube partition also may be intermittent along the tube length. Another preferred embodiment of the debris blocking structure also providing the line profile includes at least one narrow cord extending laterally across the interior of the delivery tube at or slightly recessed into or slightly protruding from the tube first end.
2. Description of the Prior Art
The modern drinking straw was invented in 1888 by Marvin Stone, a manufacturer of paper cigarette holders. Reasoning that people would enjoy drinking lemonade through a straw, Stone designed an 8½ inch paper straw with a diameter just wide enough to prevent a lemon seed from lodging in the tube. Prior to Stone's patented invention, people drank through natural grass straws. Unfortunately, the natural straws—often cut from rye—tended to make the drink taste like grass.
The straw is ideal for iced tea as well as any drink that may contain seeds, pits, pulp or other non-liquid objects. Americans drink iced tear at an astonishing rate of 35 billion gallons per year, and this rate is growing. Nearly 80% of all tea consumed in the United States is consumed over ice. Iced tea was officially created in 1904 at the World's Fair in St. Louis and has become a truly American beverage.
As Americans becoming more health-conscious, iced tea is becoming the lunchtime beverage-of-choice. Besides being a refreshing and relaxing beverage, iced tea is fat-free, contains no calories or cholesterol, and can be caffeine-free as well. Tea also has antioxidants often found in fruits and vegetables.
Iced tea served at commercial dinning facilities is almost universally served with a straw and 95% of the time with fresh lemon. As a result, the problem of lemon (citrus) seeds entering straws has become very common.
In addition, many restaurants serve drinking water with sliced lemons or limes placed into the glass.
Non-liquid objects such as seeds, pits, pulp and ice pieces readily enter the common drinking straw. This may cause a variety of problems, including:
1. Drawing a non-liquid object such as a seed through the straw and into the mouth of the drinker. This may lead to several situations that could be avoided such as:                A. The non-liquid object can enter the trachea (wind pipe). This can cause a serious, life-threatening choking situation and even death.        B. An object such as a hard seed may be taken into the mouth and break or injure teeth or dental appliances.        C. The object being taken into the mouth may have a poor taste requiring the patron to spit out the object. This may be considered offensive or embarrassing to the patron and leave the patron with a poor experience of the product and the establishment.        D. In people having either diverticulosis or diverticulitis, eating seeds and pits may be medically contraindicated.        
2. The object may wedge or lodge in the straw and thereby render the straw inoperable, requiring the use of another straw cylinder or shaft to clear the straw, adding expense.
3. The drinker may attempt to clear the straw by blowing into the straw or using his or her hands or other tools or utensils to force out the lodged object. This may be objectionable for reasons such as sanitary concerns and decorum.
Prior drinking straws have included that of D'Auguste, et al., U.S. Pat. No. 5,094,861, issued on Mar. 10, 1992, for a flavored drink straw. D'Auguste, et al., including a drinking tube containing a series of powdered flavoring within honeycombed metering chambers. These chambers do not appear to define debris barriers at tube ends.
Shafik, U.S. Pat. No. 6,142,384, issued on Nov. 7, 2000, discloses a personal portable liquid filter device. The Shafik filter is fitted over the immersed end of a drinking straw to remove impurities from water. Shafik is not suitable for blocking entry of seeds and similar debris in a beverage because it would create substantial flow resistance and may remove beverage flavor, and because it would be expensive to manufacture as part of a drinking straw.
Barley, U.S. Pat. No. 3,389,803, issued on Jun. 25, 1968, teaches an orally operable water filter. Barley includes a hollow tubular filter housing having a mouthpiece on one end adapted to be engaged by user lips and a pair of spaced filter plates which retain activated carbon and a bacteria filter within the housing opposite the mouthpiece. Dyer, U.S. Pat. No. 1,000,332, issued on Aug. 8, 1911, reveals a pocket filter containing filter material. The problems of Shafik are again presented if used for drinking beverages.
Vaiano, et al., U.S. Pat. No. 6,811,036, issued on Nov. 2, 2004, discloses a drinking straw with an integral filtration system. The filtration structure of Vaiano, et al., is located in the middle region of the straw, so that debris could enter the straw and become lodged against the filtration structure. And, in addition, the problems of Shafik are presented. Martin, U.S. Pat. No. 580,527, issued on Apr. 13, 1897, teaches a drinking tube having at one end a mouthpiece and at the other end a strainer secured to the periphery of a cup-like enlargement to form a chamber containing a ball. Martin would be complex and very expensive to manufacture and would inhibit beverage flow.
Villani, et al., U.S. Pat. No. 6,109,538, issued on Aug. 29, 2000, reveals a flavoring delivery drinking straw. Villani, et al., includes a delivery tube containing a flavoring capsule retained between two spaced apart screen barriers within the delivery tube middle section. Debris could enter the straw and become lodged against the barrier screens.
Manning, U.S. Pat. No. 5,718,681, issued on Feb. 17, 1998, discloses a medication delivery straw having a conical particle barrier protruding into one delivery tube end. Debris could enter and become lodged in the conical particle barrier.
Bengtsson, et al., U.S. Pat. No. D487,375, issued on Mar. 9, 2004, teaches a drinking straw having a flattened end which would obstruct beverage flow.
A variety of design patents have disclosed straw constructions which provide no substantially no debris obstructing benefits. Wang, U.S. Pat. No. D477,493, issued on Jul. 22, 2003, illustrates a drinking straw attachment having two diverging barrels. Gray, et al., U.S. Pat. No. D490,638, issued on Jun. 1, 2004, illustrates a paw shaped drinking straw. Diaz, U.S. Pat. No. D490,637, issued on Jun. 1, 2004, illustrates a drinking straw with a panel clipped to one end of a delivery tube, the panel having a stylized image of a human mouth. Cecere, U.S. Pat. No. D491,336, issued on Jun. 15, 2004, illustrates a combination lollipop straw having a lollipop simulating structure at one delivery tube end. Goodman, Jr., U.S. Pat. No. 332,198, issued on Jan. 5, 1993, illustrates a drinking straw apparently having a pellet contained between two barriers near but spaced from one delivery tube end.
It is thus an object of the present invention to provide a safety straw which permits a free flow of the beverage through the delivery tube while preventing entry of debris of a selected minimum target size into the delivery tube.
It is another object of the present invention to provide such a safety straw which the debris blocking structure is placed substantially at the tube first end, either at or immediately adjacent to the tube first end, to prevent debris from passing through the delivery tube while preventing the debris from entering the delivery tube altogether so that the debris cannot lodge and become an obstruction within the tube.
It is finally an object of the present invention to provide such a safety straw which is highly economical to manufacture.